Platelet-Rich Fibrin (PRF) is a natural, blood-derived product used in medical and aesthetic fields to promote tissue regeneration and repair. This article explains the step-by-step process of preparing PRF, including necessary equipment and important considerations.
What is Platelet-Rich Fibrin?
Platelet-Rich Fibrin is a concentrated biological product derived from a patient’s own blood. It forms a matrix rich in platelets, white blood cells, and various growth factors. Unlike other platelet concentrates, PRF does not require added anticoagulants or chemicals, relying on the blood’s natural clotting process to form a stable fibrin scaffold.
This three-dimensional network encapsulates and slowly releases growth factors like PDGF, TGF-β, VEGF, EGF, and IGF-1. These components stimulate cell regeneration, promote new blood vessel formation, and enhance tissue repair. The fibrin matrix supports cell migration and tissue regeneration, allowing for a sustained release of these molecules over several days. As an autologous material, PRF eliminates the risk of disease transmission, immune rejection, or allergic reactions, making it a valuable tool in regenerative medicine.
Essential Tools and Setup
PRF preparation requires specific equipment and a controlled environment. A specialized centrifuge is the primary tool, operating at low to moderate speeds (2,000-3,000 RPM) with adjustable RCF settings. Horizontal rotor centrifuges are beneficial as they allow blood components to settle in distinct, uniform layers, optimizing fibrin clot quality.
Blood collection tubes must be specifically designed for PRF, typically additive-free glass or specialized plastic tubes, as anticoagulants prevent natural clot formation. Standard phlebotomy kits, including sterile syringes and needles, are also necessary. A clean and sterile working area is important to prevent contamination and ensure product safety.
The PRF Preparation Process
PRF fabrication begins with precise blood collection. Using an aseptic technique, 10-15 milliliters of venous blood are drawn. Blood collection must be quick to prevent premature clotting before centrifugation.
Immediately after collection, transfer the tubes to the centrifuge without delay, ideally within 90-120 seconds. This prevents clotting before PRF processing. Tubes are spun at specific speeds and durations according to the PRF protocol. During centrifugation, blood components separate by density, forming distinct layers.
After centrifugation, three layers are visible: platelet-poor plasma (PPP) at the top, the yellowish PRF clot in the middle, and the red blood cell (RBC) layer at the bottom. The PRF layer contains concentrated platelets, white blood cells, and the fibrin matrix. The final step involves carefully harvesting the PRF clot using sterile forceps or a spatula, avoiding mixing with the RBC layer to ensure purity.
Variations in PRF Preparation
Variations in PRF protocols lead to different types, each with distinct characteristics.
Leukocyte-Platelet Rich Fibrin (L-PRF)
L-PRF is prepared by centrifuging blood at higher speeds (2,700-3,000 RPM) for 10-15 minutes. This yields a dense fibrin clot that traps platelets and a significant number of leukocytes.
Advanced PRF (A-PRF)
A-PRF uses a lower relative centrifugal force, such as 200g for approximately 8 minutes. This reduced speed results in a more porous and malleable fibrin matrix, allowing for a more even distribution of trapped platelets and immune cells. This structural difference contributes to a more sustained and gradual release of growth factors.
Injectable PRF (I-PRF)
I-PRF remains liquid for a short period after preparation, making it suitable for injection. This is achieved with even lower centrifugation speeds and shorter durations, such as 60g for 3 minutes or up to 700g for 8 minutes. I-PRF retains its liquid consistency for about 15-20 minutes before coagulating into a gel.
These variations in centrifugation parameters directly influence the final product’s consistency, cellular content, and growth factor release profile.
Important Considerations for PRF Preparation
Ensuring PRF quality, safety, and effectiveness requires careful adherence to several considerations. A strict aseptic technique is necessary at every stage, from blood collection to clot harvesting, to prevent microbial contamination. Proper handling of collected blood and prepared PRF preserves the biological activity of growth factors and cells.
The choice of blood collection tubes significantly impacts the final PRF product; additive-free glass or specialized PRF tubes are used to promote natural clotting. The type of centrifuge, whether horizontal or fixed-angle rotor, influences separation efficiency and PRF quality. While some PRF forms, like injectable types, require immediate use, solid PRF clots can be compressed into membranes or plugs. PRF preparation should always be performed by trained healthcare professionals.